A man and young girl in a centre for refugees. Photo: Giuseppe Cacace/AFP

Italy needs to improve conditions in its migrant centres to avoid health problems, corruption, and an increase in illegal immigration, the Council of Europe has warned.

The report, which was published on Wednesday, singled out child migrants as particularly vulnerable.

Ambassador Tomáš Boček, the Council's Special Representative on migration and refugees, compiled the report after an October visit to some of the Italian regions which have shouldered the burden of the influx of migrants: Como, Sicily, and Rome.

Many of the children who arrive in Italy alone are slipping through the gaps, the report warned, due to an inadequate guardianship system, poor conditions in migrant centres, and procedural delays.

The 'hotspots' which are intended to be the first port of call for newly-arrived migrants were criticized as "unfit to provide children's needs".

Despite the fact that the maximum period of time spent in these hotspots is supposed to be 72 hours, Boček said he had met youngsters in Lampedusa who had been housed there "in limbo" for over two months.

These delays led to overcrowded accommodation and poor sanitary conditions.

"In Lampedusa I also saw blocked toilets, with water leaking into the neighbouring bedroom which accommodated young girls, and the female showers were in a poor condition," the Special Representative recalled.

When children arrive in Italy without a parent or carer, the local mayor is generally appointed their guardian, but in areas which have seen high numbers of arrivals, this leaves mayors or their staff members responsible for over 1,000 children and therefore unable to provide proper care.

What's more, delays in appointing guardians, sometimes stretching over several months, created what Boček termed a "vacuum" in their care, potentially leaving them vulnerable to falling into the hands of smugglers.

The report urged Italy to implement "updated, universal standards" and regular monitoring for its migrant centres, both to ensure improvements in conditions and to minimize the risk of corruption at management level.